Hi,
On http://www.w3.org/TR/2004/WD-xhtml2-20040722/mod-styleSheet.html
you're missing a "?" in the first example in section 25.1.3.
Where it reads:
<xml-stylesheet href="mystyle.css" rel="stylesheet" type="text/css"?>
it should probably read:
<?xml-stylesheet href="mystyle.css" rel="stylesheet" type="text/css"?>
-Chris